Going along to get along

Tech brief

Jul 23, 2007

PEAK PERFORMANCE: Physicists at JILA using ultrafast lasers have confirmed subtle collective behavior among electronic structures in semiconductors. Above, matching large peaks, showing energy intensity, indicate that pairs of large electronic particles are oscillating in concert. Even at other levels of intensity, such as that shown below, the data was consistent with new theoretical models.

Traffic analysts have long known that human drivers have a strange, unreasonable tendency to clump together and create traffic jams. It seems microscopic particles in semiconductors also can exhibit crowd behavior. Researchers at JILA, a joint research venture of the National Institute of Standards and Technology and the University of Colorado at Boulder, have detected the collective-behavior effect in electrons excited with ultrafast lasers. The findings are expected to aid in the design of optoelectronic devices such as semiconductor diode lasers used in telecommunications. www.nist.gov